Flare tanks are used in oil and gas drilling operations for disposing of combustible waste gases in a manner that protects oilfield workers. For example, they are commonly used to burn off the small pockets of gas encountered during drilling. They also separate the liquids mixed with the waste gas, such as water and drilling mud, and hold them for disposal by environmentally acceptable means in order to prevent ground contamination. Prior art flare tank apparatuses are described, for example, in U.S. Pat. Nos. 5,807,095, 5,882,187 and 5,997,284 (Gustafson et al.).
Flare tanks may be portable apparatuses that are moved to job sites as needed. At a job site, the flare tank is connected to a flare line, i.e. the conduit that extends from the drill string and carries to the flare tank the liquid and combustible gases to be treated. In the prior art, a connection between the outlet end of the flare line and the inlet of the flare tank apparatus is made by welding a connecting member therebetween. The use of a welded connection increases the cost of both connecting and subsequently disconnecting the flare tank apparatus. It would be desirable to provide a flare tank apparatus having improved means for convenient connection to the flare line.